<template>
    <div>
         <div class="goods">
            <div class="menu-wrapper">
                <ul>
                  <!--current-->
                  <li class="menu-item" v-for="(good, index) in goods" :key="index"
                      :class="{current: index===currentIndex}" @click="clickMenuItem(index)">
                      <span class="text bottom-border-1px">
                        <!-- 有小图标就加载小图标，没有就不加载，以免报错 -->
                      <img class="icon" :src="good.icon" v-if="good.icon">
                      {{good.name}}
                      </span>
                  </li>
                </ul>
            </div>
            <div class="foods-wrapper">
                <ul ref="foodsUl" class="foodsUl">
                <li class="food-list-hook" v-for="(good, index) in goods" :key="index">
                    <h1 class="title">{{good.name}}</h1>
                    <ul>
                    <li class="food-item bottom-border-1px" v-for="(food, index) in good.foods"
                        :key="index" @click="showFood(food)">
                        <div class="icon">
                            <img width="57" height="57" :src="food.icon">
                        </div>
                        <div class="content">
                        <h2 class="name">{{food.name}}</h2>
                        <p class="desc">{{food.description}}</p>
                        <div class="extra">
                            <span class="count">月售{{food.sellCount}}份</span>
                            <span>好评率{{food.rating}}%</span>
                        </div>
                        <div class="price">
                            <span class="now">￥{{food.price}}</span>
                            <span class="old" v-if="food.oldPrice">￥{{food.oldPrice}}</span>
                        </div>
                        <div class="cartcontrol-wrapper">
                            <CartControl :food="food"/>
                        </div>
                        </div>
                    </li>
                    </ul>
                </li>
                </ul>
            </div> 
          <!-- 购物车结算组件 -->
          <ShopCart></ShopCart>
        </div>
        <Food :food="showMyFood" ref="food"></Food>
    </div>



</template>

<script>

import {mapActions,mapState} from 'vuex'
import CartControl from '../../../components/CartControl/CartControl'
import Food from '../../../components/Food/Food'
import ShopCart from '../../../components/ShopCart/ShopCart'
// 第一步引入
import BScroll from 'better-scroll'


export default {
    props: {

    },
    data() {
        return {
            scrollY:'', //获取实时滚动的高度
            tops:[],//获取所有food里面的li滚出去的高度
            showMyFood:{}//定义food组件的内容
        };
    },
    computed: {
        ...mapState(['goods']),
         currentIndex(){
          let {tops,scrollY} = this
          return tops.findIndex((item,index)=>{
              return scrollY>=tops[index] && scrollY<tops[index+1]
           })
             
         }
    },
    created() {

    },
    mounted() {
      // 在异步请求完数据之后 等待dom更新 后再去执行滚动监听事件
      this.$store.dispatch('getShopGoods',()=>{
        // 下一次dom更新后执行
        this.$nextTick(()=>{
              this._initScroll()
              this._initFood()

          })
      })
       
       
    },
    methods: {

        _initScroll(){
            // 第二步实例化 
            // 左边滚动
            this.menuScroll= new BScroll('.menu-wrapper',{
              probeType:2,
              click:true //可以触发点击事件
            })
            // 右边滚动
            this.foodScroll = new BScroll('.foods-wrapper',{
              probeType:3,
              click:true //可以触发点击事件
            })
            // 给右边的food绑定滚动监听事件 目的实时的可以监听到滚动的高度
            // 获取到滚动的高度 通过计算 然后来判断 当前的高度在food整个盒子的具体位置
            this.foodScroll.on('scroll',({x,y})=>{
              let scrolly = Math.abs(y)
              this.scrollY = scrolly
              // console.log(this.scrollY);
            })
            // 给右侧列表绑定scroll结束的监听
            this.foodScroll.on('scrollEnd', ({x, y}) => {
                console.log('scrollEnd', x, y)
                this.scrollY = Math.abs(y)
            })
           
        },
        _initFood(){
         
             let top = 0; //初始高度 默认是0
             let tops = [] // 存放每个Li滚出去的高度
             tops.push(top)
             // 获取每个li的高度
             let lis = this.$refs.foodsUl.children
             console.log(lis);
             Array.from(lis,(li,index)=>{
               let liHeight = li.clientHeight
              //  console.log(liHeight);
               top+=liHeight
               console.log(top);
               
               tops.push(top)
             })
             this.tops = tops
             console.log(this.tops);
             
             
              
        },
        clickMenuItem(index){
            // this.currentIndex = index
            let top = this.tops[index]
            console.log(top);
            // this.scrollY = -top
            this.foodScroll.scrollTo(0,-top,100)
        },
        showFood(food){
          this.showMyFood = food
          console.log(this.$refs.food);//找到food这个子组件 直接调用子组件里面的方法
          this.$refs.food.toggleShow()




        }
    },
    components: {
        CartControl,
        Food,
        ShopCart
    }
};
</script>

<style scoped lang='stylus' rel="stylesheet/stylus" >
 @import "../../../common/stylus/mixins.styl"
    ul 
      margin 0
      padding 0 
    li 
      list-style none

  .goods
    display: flex
    position: absolute
    top: 202px
    bottom: 46px
    width: 100%
    background: #fff;
    overflow: hidden
    .menu-wrapper
      flex: 0 0 80px
      width: 80px
      background: #f3f5f7
      .menu-item
        display: table
        height: 54px
        width: 56px
        padding: 0 12px
        line-height: 14px
        &.current
          position: relative
          z-index: 10
          margin-top: -1px
          background: #fff
          color: $green
          font-weight: 700
          .text
            border-none()
        .icon
          display: inline-block
          vertical-align: top
          width: 12px
          height: 12px
          margin-right: 2px
          background-size: 12px 12px
          background-repeat: no-repeat
        .text
          display: table-cell
          width: 56px
          vertical-align: middle
          bottom-border-1px(rgba(7, 17, 27, 0.1))
          font-size: 12px
    .foods-wrapper
      flex: 1
      .title
        padding-left: 14px
        height: 26px
        line-height: 26px
        border-left: 2px solid #d9dde1
        font-size: 12px
        color: rgb(147, 153, 159)
        background: #f3f5f7
        margin 0
      .food-item
        display: flex
        margin: 18px
        padding-bottom: 18px
        bottom-border-1px(rgba(7, 17, 27, 0.1))
        &:last-child
          border-none()
          margin-bottom: 0
        .icon
          flex: 0 0 57px
          margin-right: 10px
        .content
          flex: 1
          .name
            margin: 2px 0 8px 0
            height: 14px
            line-height: 14px
            font-size: 14px
            color: rgb(7, 17, 27)
          .desc, .extra
            line-height: 10px
            font-size: 10px
            color: rgb(147, 153, 159)
          .desc
            line-height: 12px
            margin-bottom: 8px
          .extra
            .count
              margin-right: 12px
          .price
            font-weight: 700
            line-height: 24px
            .now
              margin-right: 8px
              font-size: 14px
              color: rgb(240, 20, 20)
            .old
              text-decoration: line-through
              font-size: 10px
              color: rgb(147, 153, 159)
          .cartcontrol-wrapper
            position: absolute
            right: 0
            bottom: 12px
    
</style>
